Fountain pen



Patented Jan. 11,1938

FOUNTAIN PEN Benjamin w. nulle, Elizabeth, N. J., mimmto Eagle Pencil Company, a corporation oi' Dela- Application Auml; 13, 1935, serial No. 35,9011

4 Claims.

-My present'invention relates to fountain pens and is more especially concerned with fountain pens of the familiar vacuum filler type.

As conducive to a clear understanding of the invention, it is noted that such pens as commonly made, have in practice been subject to rapid leakage as the ink in the pen barrel approaches exhaustion. This leakage is due to the expansive pressure exerted on the relatively large body of airin the pen barrel as the same becomes heated during handling or otherwise, with the consequent rapid expulsion through the ink feed of the small residue of ink.

An object of the present invention is to provide a fountain pen of the above type in which the rate of feed remains uniformly reliable, substantially to the complete exhaustion of the ink from the barrel, and this, without resort to added parts or other complications, or enhanced cost'of prog() duction.

In the accompanying drawing, in which is shown one of various possible embodiments of the several features of the invention,

Fig. 1 is a view in longitudinal cross-section through one embodiment,

' Fig. 2 is a transverse sectional view taken on line 2-2 of Fig. 1,

Fig. 3 is a perspective View of the grip section,

Fig. 4 is alfragmentary sectional view similar to Fig. lof an alternative embodiment, and

Fig. 5 is a transverse sectional view taken on y line 5-5 of Fig. 4. y

Referring now to Figs. 1 to 3 of the drawing,

the pen in its general outline is of the conventional type shown in the expired patent to Taylor,

802,668, dated October 24th, 1905.

The pen preferably includes the barrel I0 reduced at its rear end to afford a neck I Iy about which may be aiiixed a rubber bulb I2 through which the vsuction or so-called vacuum is applied in filling. At the forward end of the barrel is the grip section I3; which may be frictionally or otherwise secured therein in liquid-tight relation.

This grip section has an axial cylindrical bore I4 into which fits the feed section I5, with the usual convexity for accommodating the pen nib I6, the shank of which is frictionally seated in the forward end of the grip section and covers the ink duct I1 which extends the entire length of the feed section and communicates with the contents of the barrel. In a corresponding socket -I8 in the rear end of the feed section is mounted the air tube I9, extending axially substantially the height of the ink barrel.` The socket I8 communicatesby means of a cross-passage 20 with alternately pressing and releasing the bulb I2.

(o1. 120g-s2) the ink duct I1 of the feed. The cap 2| is removably threaded at 22 upon the rear end of the bar-v rel to protect the bulb I2 in normal use, and the conventional fountain pen cap (not shown) can be frictionally fitted over the cap 2l or alter- 5 natively threaded at 23 over the forward end of the barrel to cover the nib when the pen is out of use. z

According to the present invention the grip section I3, instead of terminating as customarily, substantially flush with the friction fitted portion Ilia thereof, has an integral cylindrical extension 24, which protrudes upward into the barrel for a substantial distance, ordinarily in the order of -'g or 1/2 inch. In a'preferred embodiment the extension affords only slight clearance with respect to the bore of the barrel. In practice, for a barrel of conventional bore of .406 inch, the grip section extension 24 would ordinarily have an outer diameter` of .312 inch, thereby affording a cylindrical restriction passage .042 inch wide. The dimensions specified are satisfactory in use, but are intended as merely one illustrative embodiment of the invention, which is of course not confined to these precise dimensions. 25

The air tube I9 has clearance 25 with respect to the bore of the extension 24, such clearance in practice being in the order of .05 inch.

Alined with the ink duct Il, the grip section preferably has a transverse port AilI at the base of the extension for a purpose which will appear in the operation set forth.

In use, the pen is charged in the conventional way by dipping the nib into a bottle of ink and 35 As is well known, in this operation, at each suction stroke ink is drawn in and on each compression stroke air and ink are expelled, but each stroke represents a gain, inasmuch as the intake of ink on each suction stroke substantially exceeds the expulsion of ink included in the mixture of air and ink expelled on each compression stroke. This operation is in accordance with the teachings of the Taylor patent above identified.

As the contents of the barrel are consumed in use of the pen, ink is replaced by air. When the ink has been consumed to the point where the volume of air is many times the residual volume of ink, it is apparent that with rise of temperature incurred from time to time in the ordinary carrying or use of a fountain pen, the expansive pressure of the air will not, in the case of the present construction, cause undue loss of ink or excessive rapidity of feed. i

This 1S explained by the yfact that when the lnk is consumed down to the level of the top of the extension 24 not only is the residual ink volume reduced to the extent of the space occupied by the extension wall 24, but the surface exposed to the flow of this residual ink is increased by the entire superficial area of the inner and outer wall of said extension, thereby greatly increasing the resistance` to the fiow of ink. Moreover, the width of the annular passage between the air tube I9 and the bore of extension 24 is so small as to impose substantial frictional resistance to the ow of ink, and that is also true with regard to the annular passage between the bore of the barrel l0 and the outer wall of the extension 24.

It is seen that despite the presence of the wall 24, the ink nevertheless can be substantially completely drained from the pen barrel, the cavity between the extension 24 and barrel I0 being drained through the port 26.

The embodiment of Figs. 4 and 5 is generally similar to that of Figs. 1 to 3, and corresponding parts bear corresponding numerals primed.

The embodiment of Figs. 4 and 5 presents the difference that the extension 24 of the grip section has an inner, wide shallow peripheral groove 21 with which communicates the port 26' at the base of the extension 24'. This arrangement has the advantage that port 26 is in communication with the ink duct Il without need for the alinement required in the embodiment of Figs. 1 to 3 between port 26 and ink duct I1. 'Ihe operation of the embodiment of Figs. 4 and 5 is identical with that of Figs. 1 to 3.

It is ofcourse understood that the invention may be embodied in various conventional types of so-called vacuum filler pens, regardless Whether use is made of the conventional bulb i2, illustratively shown, or of any of various known equivaient piston or plunger constructions suitable for the purpose.

.It will thus be seen that there is herein described an article in which the several features of this invention are embodied, and which article in its action attains the various objects of the invention and is well suited to meet the requirements of practical use.

As many changes could be made inthe above construction, and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Leters Patent is:

1. A fountain pen of the vacuum filler type, comprising a barrel having suction applying means at the outer end thereof and having a grip section at the forward end thereof, a feed section frictionally fitted in said grip section and having a restricted ink passage therealong in communication with the barrel, an air tube secured in said feed section and protruding into said barrel and having communication at its outer end with the ink passage of the feed section, said grip section having an extension protruding into the barrel, of diameter slightly less than the bore of the barreL'and slightly greater than the outer diameter of the lower end of the air tube encircled thereby and thereby resisting the es.

cape of the ink from the barrel to the feed section.

2..A fountain pen of the vacuum filler type, comprising a barrel having suction applying means at the outer end thereof and having a grip section at the forward end thereof, a feed section frictionally fitted in said grip section and having a restricted ink passage therealong in communication with the barrel, an air tube secured in said feed section and protruding into said barrel and having communication at its outer end with the ink passage of the feed section, said grip section having an extension protruding into the barrel of diameter slightly less than the bore of the barrel, a port through the lower end of said extension to permit drainage of ink fromv the restriction passage about said extension to the feed section, the inner wall of said extension having clearance with respect to the outer wall of the air tube encircled thereby.

3. As an article of manufacture for use in a vacuum filler fountain pen, a grip section having a bore therein, a feed section frictionally fitted therein, said feed section having a narrow ink feeding duct longitudinally thereof, an air tube carried by said feed section, a transverse passage through said feed section affording communication from said air tube to said ink feeding duct, said grip section having a median portion adapted for attachment into a pen barrel and having a `somewhat reduced cylindrical extension thereabove, affording a cylindrical passage with respect to said barrel, of in the order of .04 inch said extension having a transverse port at the junction between the grip mounting portion and the extension.

4. A vacuum filler fountain pen of the type comprising a barrel, a grip section securely fixed therein having an extension portion at the rear end thereof affording clearance with respect to the bore of the barrel, a feed section in said grip section, an ink duct longitudinally of the feed section, an air tube axially of the feed section and protruding into the barrel, a transverse passage aiording communication between the air tube and the ink duet, a peripheral groove in the interior of said extension near the lower end thereof, communicating with the ink duct, and a -port near the lower end of the extension communicating with said groove.

BENJAMIN W. HANLE. 

